"Зелений" синтез етилових естерів 4-гідрокси-2-оксо-1,2-дигідрохінолін-3-карбонових кислот

• Datum: 2013
• Hauptverfasser: Ukrainets, I. V., Gorokhova, O. V., Andreeva, X. V., Golik, N. Yu.
• Format: Artikel
• Sprache: English
• Veröffentlicht: National University of Pharmacy 2013
• Schlagworte: естер 4-гідрокси-2-оксо-1; 2-дигідрохінолін-3-карбоксилатів; піридо[3; 2; 1-ij]-хіноліни; пі- роло[3; 3-(1-хінолініл)пропаннітрили; «зелена хімія»; УДК 547.298.1; 547.831.9; 615.254.1; 615.276
• Online Zugang: https://ophcj.nuph.edu.ua/article/view/ophcj.13.750
• Назва журналу: Journal of Organic and Pharmaceutical Chemistry

One of the most convenient methods for obtaining ethyl of N-substituted 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylates and their tricyclic analogues at present is condensation of the corresponding anilines with triethyl methanetricarboxylate. In spite of the fact that there are many methods describing the successful performance of this reaction in conditions of laboratory, but unfortunately, all of them appeared to be completely unusable for large production for a variety of reasons. The study of quality of the esters of 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids by HPLC has shown that all of them contain from 2.4 to 5.6% of specific admixtures of 4-hydroxy-1,2-dihydroquinolin- 2-ones. In laboratory conditions these amounts can be neglected, but for industrial manufacture they can turn into great losses. The source of admixtures of 4-hydroxy-1,2-dihydroquinolin-2-ones appearing in crude esters can be only the esters themselves. It is obvious that ester grouping is partially destroyed not in the process of separation of the final products, but during the course of the basic reaction. It has been experimentally proven that the cause of contamination of the target products with the admixtures of the corresponding 4-hydroxy-1,2-dihydroquinolin-2-ones is water, which is present in reagents. Applying the principles of «green chemistry» the alternative for carrying out the syntheses of ethyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylates adapted for industrial manufacture has been suggested on the basis of N-substituted anilines and triethyl methanetricarboxylate.